The stakes are enormous, writes Hannah Francis.
The Terminator analogies are inevitable, but Toby Walsh says we're still a good 50 years away from having killer robots quite as sophisticated as that. 
In fact, it's the "stupid" nature of technologies being used in the "third wave" of warfare, known as autonomous weapons systems - "killer robots" for short - that has him worried. Very worried.
Only a few days ago, an anonymous whistleblower, already dubbed the "second Snowden", leaked classified US military material detailing its use of drones in warfare.
The "drone papers", published in The Intercept, revealed that in a five-month period during a US operation in Afghanistan, nearly 90 per cent of people killed in drone strikes were not the intended targets.
Without human intervention, Walsh says, that figure would be "even worse, guaranteed".
Though he calls himself an "accidental activist", the UNSW artificial intelligence professor and researcher at Data61 (formerly NICTA) sees it as his scientific duty to inform humanity of the impending, self-imposed peril.
Walsh was a major driving force behind the open letter calling for a ban on killer robots that was signed by Stephen Hawking, Elon Musk and more than 2000 AI researchers in   July, helping bring significant media attention to the issue. Non-governmental organisations (NGOs), including Human Rights Watch, have campaigned on the issue since 2012 under the umbrella group Stop Killer Robots.
Walsh and his colleagues fear an arms race in autonomous weapons could have disastrous consequences. The risk is that these weapons will fall into the hands of enemies including terrorists and rogue states. A worst-case scenario would be swarms of cheap, terrifying, autonomous weapons - which cannot compute the ethics or intricacies of warfare - flooding the market and being unleashed upon innocent people. It's not going to be "clean", simulated warfare with robots killing robots.
"Wars are very asymmetric; they're not fought between nation and nation, but against terrorists, rogue nations, etcetera. They're not going to sign up to 'gentlemen's rules', otherwise why not just settle it with a chess match or tiddlywinks?
"We need to start acting now."
Walsh is in New York this week to discuss the issues and answer ambassadors' questions at a side event at the United Nations' First Committee on Disarmament and International Security, which meets annually in   October.
While several nations have openly supported a ban on lethal autonomous weapons, the big names - the US, Britain, Israel, China - are missing from the list. Australia has yet to make a formal statement on where it stands. The Department of Defence was contacted for comment but did not respond in time for publication.
Walsh says so-called killer robot technology is "technically feasible" today, even if countries aren't deploying it just yet. Realistically, they could be doing so within a few years.